In text books, we find many concepts and the corresponding
explanations. In relation with concepts, authors introduce terminologies. It is
natural to make source codes for the terminologies. Integration of the codes is
Science Code .Net. There are many examples of problems in text books in order to
exercise students in understanding concepts. As far as students understand the
concepts or the terminologies in some subject, they should solve exercises using
Science Code .Net without pencil and paper. The purpose of using Science Code
.Net is not simply to solve a problem, but to make students acquaint with
object-oriented programming for Science. Thus, the role of Science Code .Net is
to provide us with a library with which one can solve exercise problems given in
text books.

As an example, we present how to solve a set of linear
equations in Calculus.
The famous text book for Calculus may be the book written by S. Lang.
Using terminologies in the book, we have to use the names of
Matrix and Vector. We here present the source codes to solve:

2.0 x
+ 4.0 y + 3.0 z = 5.3

1.0 x + 4.0 y
+ 3.0 z = 6.3

1.0 x + 4.0 y + 8.0 z
= 7.3

In the following code, we use the class LinearEquation which is constructed by using
a Matrix and a Vector:

using

System;

using

L=Science.Mathematics.LinearAlgebra;

namespace

ScienceTest.MathematicsTest.LinearAlgebraTest

{

///<summary>

///
LinearEquationTest

///</summary>

publicclassLinearEquationTest

{

public LinearEquationTest()

{

}

privatestring
result;

publicstring
Result

{

get{return
result;}

}

publicvoid
Compute()

{

double[,] a = newDouble[3,3];

a[0,0]=2.0;

a[0,1]=4.0;

a[0,2]=3.0;

a[1,0]=1.0;

a[1,1]=4.0;

a[1,2]=3.0;

a[2,0]=1.0;

a[2,1]=4.0;

a[2,2]=8.0;

L.Matrix m = new L.Matrix(a);

double[] c = newDouble[3];

c[0] = 5.3;

c[1] = 6.3;

c[2] = 7.3;

L.Vector v = new L.Vector(c);

L.

LinearEquation
eq = new L.LinearEquation(m,v);

eq.Solve();

foreach(double
k in eq.Solution)

result += k.ToString()+"\r\n";

}

}

}

Then we can get the result in the string of
Result.
-1
1.675
0.2

As another example, we present a problem in Physics.
Using the textbook written by R. Serway, we denote
many class names. Using the classes
Circuit, ElectricCurrent, ElelctricPotential in Science.Physics.GeneralPhysics,
we find the currents I1, I2, I3 in the
circuit shown as the following figure:

using

System;

using

GP =
Science.Physics.GeneralPhysics;

namespace

ScienceTest.PhysicsTest.GeneralPhysicsTest

{

///<summary>

///
KirchhoffTest

///</summary>

publicclassCircuitTest

{

public CircuitTest()

{

}

privatestring
result;

publicstring
Result

{

get{return
result;}

}

publicvoid
Compute()

{

GP.Circuit cir =
new GP.Circuit();

cir.NumberOfJunctions = 2;

GP.ElectricPotential[]
V = new GP.ElectricPotential[2];

V[0] = new GP.ElectricPotential();

V[0].V = 0.0;

V[1] = new GP.ElectricPotential();

V[1].VariableQ = true;

cir.PotentialAtJunction = V;

cir.NumberOfSegments = 3;

GP.ElectricCurrent[]
I = new GP.ElectricCurrent[3];

I[0] = new GP.ElectricCurrent();

I[0].VariableQ = true;

I[0].FromJunction = 0;

I[0].ToJunction = 1;

I[1] = new GP.ElectricCurrent();

I[1].VariableQ = true;

I[1].FromJunction = 0;

I[1].ToJunction = 1;

I[2] = new GP.ElectricCurrent();

I[2].VariableQ = true;

I[2].FromJunction = 1;

I[2].ToJunction = 0;

cir.Current = I;

cir.Segment = 0;

GP.ElectricPotentialDifference
v1

= new GP.ElectricPotentialDifference();

v1.V = 10.0;

GP.Resistance r1 =
new GP.Resistance();

r1.Ohm = 6.0;

cir.Add(v1);

cir.Add(r1);

cir.Segment = 1;

GP.ElectricPotentialDifference
v2

= new GP.ElectricPotentialDifference();

v2.V = -14.0;

GP.Resistance r2 =
new GP.Resistance();

r2.Ohm = 4.0;

cir.Add(v2);

cir.Add(r2);

cir.Segment = 2;

GP.Resistance r3 =
new GP.Resistance();

r3.Ohm = 2.0;

cir.Add(r3);

cir.KirchhoffRule();

result += Convert.ToString(I[0].A)+"\r\n"+

Convert.ToString(I[1].A) + "\r\n " +

Convert.ToString(I[2].A) + "\r\n " +

Convert.ToString(V[0].V) + "\r\n " +

Convert.ToString(V[1].V) + "\r\n ";

}

}

}

Then, we can see the results in the
string of Result. Once again, it should be emphasized that the exercise problems
are solved by using the single library, Science.dll.